From: Rolf Bjarne Kvinge <rolf@xamarin.com>
Date: Wed, 6 Jan 2016 12:56:43 +0000 (+0100)
Subject: [aot] Fix emission of external aot data by aligning tables in the file.
X-Git-Url: http://wien.tomnetworks.com/gitweb/?p=mono.git;a=commitdiff_plain;h=45a86f2116bd4188c16b4ba13ac2b177054cf6bb

[aot] Fix emission of external aot data by aligning tables in the file.

The table reading code depends on data being aligned, so make sure it is.
---

diff --git a/mono/mini/aot-compiler.c b/mono/mini/aot-compiler.c
index 63a330d5370..b066a590993 100644
--- a/mono/mini/aot-compiler.c
+++ b/mono/mini/aot-compiler.c
@@ -2338,6 +2338,12 @@ emit_aot_data (MonoAotCompile *acfg, MonoAotFileTable table, const char *symbol,
 		acfg->table_offsets [(int)table] = acfg->datafile_offset;
 		fwrite (data,1, size, acfg->data_outfile);
 		acfg->datafile_offset += size;
+		// align the data to 8 bytes. Put zeros in the file (so that every build results in consistent output).
+		int align = 8 - size % 8;
+		acfg->datafile_offset += align;
+		guint8 align_buf [16];
+		memset (&align_buf, 0, sizeof (align_buf));
+		fwrite (align_buf, align, 1, acfg->data_outfile);
 	} else if (acfg->llvm) {
 		mono_llvm_emit_aot_data (symbol, data, size);
 	} else {